Federal health advisers have voted against a Merck proposal to sell its prescription respiratory pill Singulair as an over-the-counter allergy medication.
The Food and Drug Administration's panel of experts voted 11-4 Friday against making the drug available without a prescription. Merck sells Singulair via prescription for asthma and allergies.
Singulair was once Merck's best-selling drug, but sales have plummeted since the drug's patent expired in mid-2012, exposing the brand to low cost generics.
Merck & Co. Inc. hopes to revive sales of the former blockbuster as an over-the-counter allergy medication.
But FDA's advisers said the safety of Singulair as an over-the-counter treatment has not been established, particularly since patients could use it off-label for more serious conditions like asthma.
The FDA is not required to follow the expert panel's vote.